Machine-Learning-Based Password-Strength-Estimation Approach for Passwords of Lithuanian Context

In an information-security-assurance system, humans are usually the weakest link. It is partly related to insufficient cybersecurity knowledge and the ignorance of standard security recommendations. Consequently, the required password-strength requirements in information systems are the minimum of what can be done to ensure system security. Therefore, it is important to use up-to-date and context-sensitive password-strength-estimation systems. However, minor languages are ignored, and password strength is usually estimated using English-only dictionaries. To change the situation, a machine learning approach was proposed in this article to support a more realistic model to estimate the strength of Lithuanian user passwords. A newly compiled dataset of password strength was produced. It integrated both international- and Lithuanian-language-specific passwords, including 6 commonly used password features and 36 similarity metrics for each item (4 similarity metrics for 9 different dictionaries). The proposed solution predicts the password strength of five classes with 77% accuracy. Taking into account the complexity of the accuracy of the Lithuanian language, the achieved result is adequate, as the availability of intelligent Lithuanian-language-specific password-cracking tools is not widely available yet.